Image forming apparatus

ABSTRACT

The image forming apparatus comprises a replaceable consumable, a determination unit for determining whether the consumable is non-genuine (S 12 ), a first image-quality adjustment unit, and a second image-quality adjustment unit. When the determination unit determines that the consumable is non-genuine (YES in S 12 ), the first image-quality adjustment unit performs an image-quality adjustment suitable for the non-genuine consumable (S 13 ). When the determination unit determines that the consumable is genuine (No in S 12 ), the second image-quality adjustment unit performs an image-quality adjustment suitable for the genuine consumable (S 14 ).

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to an image forming apparatus, and moreparticularly relates to an image forming apparatus that uses replaceableconsumables.

2. Description of Background Art

When an image forming apparatus is used as a copying machine, anelectrostatic latent image is formed on a photoreceptor, a toner issupplied to be adhered to the electrostatic latent image in order tomake it visible, and the image is transferred with the toner onto asheet of paper to produce an output image. Outputs of images consumetoner, and therefore the consumed toner should be supplied from outsidesupply sources. Generally, the consumed toner is supplied by replacingthe empty toner cartridge with a toner cartridge filled with toner.

Toner serves as a component for forming images and has various features.For example, toner has a charging performance and a particle sizedistribution to improve the image quality. The surface property of tonerfunctions to prevent a photoreceptor and a developing unit from damage.The features that the toner should have depend on the image formingapparatus and the photoreceptor and developing unit contained therein.Specifically, the use of genuine toner suitable for the image formingapparatus prevents the photoreceptor and other units from damage and cancreate high-quality images. These sorts of toner are manufactured bypeople well-versed in the toner features, such as manufacturers of theimage forming apparatuses.

However, some people, who are ill-versed in the toner features,manufacture and sell toner. Such “non-genuine toner” that is formed byanalyzing and imitating toner manufactured by the image formingapparatus manufacturer, that is to say “genuine toner”, is passable toform visible images. However, because non-genuine toner does not haveexactly the same features as genuine toner, it is very difficult toobtain high-quality images with the use of non-genuine toner. Besides,such non-genuine toner may badly wear the photoreceptor, for example,resulting in failure of the image forming apparatus.

Japanese unexamined patent publication No. 2001-125462 discloses atechnique to determine whether a cartridge is an improper cartridge thathas been refilled with consumables. The image forming apparatusaccording to the publication is designed to detect whether or not thecartridge loaded in the image forming apparatus is proper, and prohibitthe printing operation when the cartridge is improper.

Most users who use the non-genuine toner to output images hardly noticethe above-described failure caused by the non-genuine toner. This putsusers at a disadvantage. In addition, the use of non-genuine toner inthe same manner as genuine toner does not provide high-quality images.

SUMMARY OF THE INVENTION

The present invention has an object to provide an image formingapparatus capable of forming images of as good quality as possible evenif the consumable is non-genuine and reducing the possibility offailures.

The image forming apparatus according to the present invention comprisesa replaceable consumable, a determination unit for determining whetherthe consumable is non-genuine, and a first image-quality adjustment unitfor adjusting image quality. When the determination unit determines thatthe consumable is non-genuine, the first image-quality adjustment unitperforms an image-quality adjustment suitable for the non-genuineconsumable.

More preferably, the consumable is provided with an IC tag storinginformation that the consumable is genuine. The determination unit readsthe information stored in the IC tag and determines whether theconsumable is non-genuine or genuine based on the information.

More preferably, the consumable includes a toner cartridge filled withtoner. The first image-quality adjustment unit adjusts image quality bysupplying toner that adheres to an electrostatic latent image used foradjusting the image quality. The electrostatic latent image is formed ona photoreceptor.

More preferably, the first image-quality adjustment unit adjusts imagequality by increasing aging time.

More Preferably, the image forming apparatus comprises a secondimage-quality adjustment unit. When the determination unit determinesthat the consumable is genuine, the second image-quality adjustment unitperforms an image-quality adjustment suitable for the genuineconsumable. The consumable includes a toner cartridge filled with toner.The first image-quality adjustment unit adjusts image quality bysupplying non-genuine toner that adheres to a first electrostatic latentimage including a plural number of pattern images and used for adjustingthe image quality. The first electrostatic latent image is formed on aphotoreceptor. The second image-quality adjustment unit adjusts imagequality by supplying genuine toner that adheres to a secondelectrostatic latent image including a plural number of pattern imagesand used for adjusting the image quality. The second electrostaticlatent image is formed on a photoreceptor. The number of pattern imagesincluded the first electrostatic latent image is larger than the numberof pattern images included the second electrostatic latent image.

More Preferably, the image forming apparatus comprises a secondimage-quality adjustment unit. When the determination unit determinesthat the consumable is genuine, the second image-quality adjustment unitperforms an image-quality adjustment suitable for the genuineconsumable. The consumable includes a toner cartridge filled with toner.The first image-quality adjustment unit adjusts image quality bysupplying non-genuine toner that adheres to a first electrostatic latentimage including a plural number of strip-shaped pattern images and usedfor adjusting the image quality. The first electrostatic latent image isformed on a photoreceptor. The second image-quality adjustment unitadjusts image quality by supplying genuine toner that adheres to asecond electrostatic latent image including a plural number ofstrip-shaped pattern images and used for adjusting the image quality.The second electrostatic latent image is formed on a photoreceptor. Anarea of pattern images included the first electrostatic latent image islarger than an area of pattern images included the second electrostaticlatent image.

More Preferably, the image forming apparatus comprises a secondimage-quality adjustment unit. When the determination unit determinesthat the consumable is genuine, the second image-quality adjustment unitperforms an image-quality adjustment suitable for the genuineconsumable. The consumable includes a toner cartridge filled with toner.The first image-quality adjustment unit adjusts image quality bysupplying non-genuine toner that adheres to a first electrostatic latentimage including a plural number of pattern images that have differencesin surface potential thereamong and used for adjusting the imagequality. The first electrostatic latent image is formed on aphotoreceptor. The second image-quality adjustment unit adjusts imagequality by supplying genuine toner that adheres to a secondelectrostatic latent image including a plural number of pattern imagesthat have differences in surface potential thereamong and used foradjusting the image quality. The second electrostatic latent image isformed on a photoreceptor. A difference in surface potential of patternimages thereamong included the first electrostatic latent image issmaller than a difference in surface potential of pattern imagesthereamong included the second electrostatic latent image.

According to the present invention, when the consumable is determined tobe non-genuine, an image-quality adjustment suitable for the non-genuineconsumable is performed. Therefore, even if the consumable isnon-genuine, it is possible to form images of as good quality aspossible.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of the general structure of a multifunctionalprinter according to an embodiment of this invention.

FIG. 2 is a schematic cross-sectional view of an image forming sectionthat is cross-sectioned by a plane perpendicular to a rotation axis of aphotoreceptor and lying in the middle of the image forming section.

FIG. 3 is a flow chart illustrating the operation of a controller when atoner cartridge is loaded.

FIG. 4 illustrates a part of an electrostatic latent image, formed onthe photoreceptor, for non-genuine toner cartridges.

FIG. 5 illustrates a part of an electrostatic latent image, formed onthe photoreceptor, for genuine toner cartridges.

FIG. 6 is a flow chart illustrating the operation of the controller torewrite the value of a down counter into an IC tag.

DESCRIPTION OF PREFERRED EMBODIMENT

An embodiment of the present invention will be described below byreferring to the drawings. FIG. 1 is a block diagram showing thestructure of a multifunctional printer 10 to which an image formingapparatus according to the embodiment of the invention is applied.Referring to FIG. 1, the multifunctional printer 10 includes acontroller 11 for controlling the entire multifunctional printer 10,DRAM 12 for reading and writing image data or other data, an operatingsection 13 containing a display for indicating information stored in themultifunctional printer 10 and serving as an interface between themultifunctional printer 10 and a user, an original feeder 14 forautomatically transferring an original to a predetermined readingposition, an image reader 15 including a scanner that reads the image ofthe original transferred by the original feeder 14 at the predeterminedreading position, an image forming section 16 for forming an image basedon the image of the original scanned by the image reader 15, a hard disk17 for storing the image data and so on, a FAX communication section 18connected to a public line 20, and a network IF (interface) 19 forconnecting the multifunctional printer 10 and a network 21.

The controller 11 compresses and encodes data of the original fed by theimage reader 15 and writes the encoded data in the DRAM 12. Thecontroller 11 also reads out the data written in the DRAM 12 anddecompresses and decodes the read-out data to output from the imageforming section 16.

When the multifunctional printer 10 is activated as a copying machine,the multifunctional printer 10 forms an image in the image formingsection 16 based on original image data which is read by the imagereader 15 and sent through the DRAM 12. When the multifunctional printer10 is activated as a printer, the multifunctional printer 10 forms animage in the image forming section 16 based on original image data whichis transmitted from personal computers 22 connected to the network 21through the network IF 19 and the DRAM 12. Furthermore, when themultifunctional printer 10 is activated as a facsimile machine, themultifunctional printer 10 forms an image in the image forming section16 based on image data transmitted from the public line 20 through theFAX communication section 18 and the DRAM 12, while transmittingoriginal image data, which is read by the image reader 15, through theDRAM 12 and the FAX communication section 18 to the public line 20.

In FIG. 1, double-line arrows indicate flows of image data, whilethin-line arrows indicate flows of control signals or control data.

FIG. 2 is a schematic cross-sectional view of the image forming section16 in the multifunctional printer 10, the image forming section 16 beingcross-sectioned by a plane perpendicular to a rotation axis of aphotoreceptor. Referring to FIGS. 1 and 2, the image forming section 16comprises a developing unit 23, a photoreceptor (not shown), a tonercartridge 24 and a reader 25.

The image forming section 16 supplies toner from the developing unit 23onto the surface of the photoreceptor on which light is irradiated andan electrostatic latent image is formed in order to develop the image.The developing unit 23 contains a developer (not shown). The developerin use is a two-component developer composed of toner particles andmagnetic carrier particles. With the developing process, toner in thedeveloping unit 23 is consumed and then toner in the toner cartridge 24is supplied into the developing unit 23 by the amount of the tonerconsumed.

The toner cartridge 24 is mounted on the upper part of the developingunit 23. The toner cartridge 24 is filled with toner which will beconsumed in the developing unit 23. The toner is supplied from the tonercartridge 24 through a toner supply port 27 into the developing unit 23by means of a rotatable supply roller 28 provided in the toner cartridge24. The toner supplied in the developing unit 23 is transferred tocertain parts in the developing unit 23 by means of a rotatable transferroller 29 provided in the developing unit 23, while being mixed with thecarrier particles in the developing unit 23 to carry an electric charge.

The amount of toner remaining in the toner cartridge 24 is detected by aremaining toner detection sensor 30 provided on the developing unit 23.The toner cartridge 24 is replaceable. Specifically, a user can replacean empty toner cartridge 24 with a new toner cartridge 24 filled withtoner.

The toner cartridge 24 is provided with an IC tag 26. The IC tag 26 ispositioned on the outside of the toner cartridge 24 and where the reader25 can read it. The IC tag 26 stores information regarding the tonercartridge 24, which can validate that the toner cartridge 24 is agenuine product. The information regarding the toner cartridge 24includes the specification of the toner filled in the toner cartridge24, the manufacturer, date of manufacture and so on. The reader 25 canread out the information stored in the IC tag 26 and write informationinto the IC tag 26.

Accordingly, the determination of whether the toner cartridge 24 isgenuine or not can be easily and reliably made by reading out theinformation stored in the IC tag 26. Here, “a genuine toner cartridge24” refers to a toner cartridge that is provided with an IC tag 26storing true information. Whether stored information is true or not isdetermined by reading the contents of the IC tag 26. On the other hand,“a non-genuine toner cartridge 24” refers to a toner cartridge that isnot provided with the IC tag 26 or a toner cartridge that is providedwith an IC tag 26 storing wrong information.

Next, a description will be made about the process in which a new tonercartridge 24 is loaded and an image is formed. FIG. 3 is a flow chartillustrating the operation of the controller 11 in the process.Referring to FIGS. 1 to 3, a new toner cartridge 24 is set in themultifunctional printer 10 and loaded (step S11 in FIG. 3, andhereinafter “step” will be omitted).

When the controller 11 recognizes that the toner cartridge 24 is loaded,the controller 11 determines whether the loaded toner cartridge 24 isnon-genuine or not, in other words, whether the loaded toner cartridge24 is a non-genuine product or genuine product (S12). Specifically, thecontroller 11 determines whether the reader 25 can read information ofthe IC tag 26 attached to the toner cartridge 24 and further whether theinformation of the IC tag 26 read by the reader 25 is true or not.

If there is no IC tag 26 on the toner cartridge 24, the controller 11determines that the loaded toner cartridge 24 is non-genuine because thereader 25 cannot read the information of the IC tag 26. The controller11 also determines that the loaded toner cartridge 24 is non-genuinewhen the information read out from the IC tag 26 is wrong. When theinformation read out from the IC tag 26 is true, the controller 11determines that the toner cartridge 24 is genuine. In this step, thecontroller 11, reader 25 and IC tag 26 operate as a determination unit.

Next, a description will be made about the process when the tonercartridge 24 is determined to be non-genuine. When the controller 11determines that the toner cartridge 24 is non-genuine (YES in S12), afirst image-quality adjustment unit adjusts image quality (S13). Theimage-quality adjustment by the first image-quality adjustment unitincludes irradiation of light onto the charged photoreceptor to form afirst electrostatic latent image used for adjusting image quality. FIG.4 illustrates one example of the first electrostatic latent image whichis used for adjusting image quality and formed on the photoreceptor.Referring to FIG. 4, the first electrostatic latent image on thephotoreceptor 31 includes five strip-shaped pattern images 32 a, 32 b,32 c, 32 d, and 32 e. Each of the pattern images 32 a to 32 e has alarge area. The pattern images 32 a to 32 e are formed so as to have nogreat differences in surface potential thereamong.

Because the features of the non-genuine toner are unclear, it isuncertain if the toner can create good-quality images. For example, evenif the toner may be able to create a good-quality image on a part of thesurface of the photoreceptor 31, the image quality could be deterioratedon the other parts. Therefore, the pattern images 32 a to 32 e should belarge enough to adjust the image quality. In addition, a certain largedegree of the surface-potential differences may be able to provide agood-quality image, however, the small surface-potential differences maybe not allowed to form good-quality images. Therefore, the image-qualityadjustment should be made using the pattern images with smalldifferences in surface potential thereamong.

Then the non-genuine toner is adhered to thus formed pattern images 32 ato 32 e. The non-genuine toner, which has been charged in the developingunit 23, is attracted according to the surface potentials of the patternimages 32 a to 32 e. Next, a density sensor (not shown) provided in theimage forming section 16 detects the density of the non-genuine toneradhered to each of the pattern images 32 a to 32 e. Then, the tonerdensity figured out from the surface potentials of the pattern images 32a to 32 e formed on the photoreceptor 31 is compared with the tonerdensity detected by the density sensor in order to obtain the differencebetween them. The controller 11 determines whether the differencebetween the toner densities is in an acceptable range. In other words,the controller 11 determines whether the difference is in a range wherea good-quality image is available.

When the difference is not in the acceptable range, the charge quantityof the non-genuine toner is adjusted, for example. Specifically, thecharge quantity can be adjusted by increasing the aging time, in otherwords, a time period to rotate an agitation roller (not shown) in thedeveloping unit 23. By sufficiently mixing the toner particles andcarrier particles in the developing unit 23, the toner particles aretriboelectrically charged and further increase their charge quantity.After the charge quantity of the toner is increased in this way, thesame steps mentioned above are performed to compare the toner densitiesand obtain the difference between them. This image-quality adjustmentwill be repeatedly performed until the toner density falls within theacceptable range. If the toner density does not fall in the acceptablerange even after the same steps have been done several times, imageforming conditions to obtain an image of as good quality as possible isderived. The image-quality adjustment is thus performed for thenon-genuine toner. Here, the controller 11 operates as the firstimage-quality adjustment unit. The first image-quality adjustment unitis activated at predetermined times, for example, at a time when themultifunctional printer 10 is turned on.

Accordingly, this multifunctional printer 10 can form images of as goodquality as possible for the non-genuine toner.

Next, a description will be made about the process when the tonercartridge 24 is determined to be genuine. When the controller 11determines that the toner cartridge 24 is genuine (NO in S12), a secondimage-quality adjustment unit adjusts image quality (S14). FIG. 5illustrates one example of a second electrostatic latent image which isused for adjusting the image quality and formed on the photoreceptor inorder for the second image-quality adjustment unit to adjust the imagequality. FIG. 5 corresponds to FIG. 4. Referring to FIG. 5, the secondelectrostatic latent image used for adjusting image quality includesthree strip-shaped pattern images 33 a, 33 b and 33 c. Each of thepattern images 33 a to 33 c has less area than each of the patternimages 32 a to 32 e. The pattern images 33 a to 33 c are so formed as tohave greater differences in surface potential thereamong than thepattern images 32 a to 32 e. In other words, the number of patternimages included the first electrostatic latent image is larger than thenumber of pattern images included the second electrostatic latent image.An area of pattern images included the first electrostatic latent imageis larger than an area of pattern images included the secondelectrostatic latent image. A difference in surface potential of patternimages thereamong included the first electrostatic latent image issmaller than a difference in surface potential of pattern imagesthereamong included the second electrostatic latent image. The processafter the formation of the electrostatic latent image is the same as theone the first image-quality adjustment unit has done. The image-qualityadjustment for the genuine toner is made in this way. Here, thecontroller 11 operates as a second image-quality adjustment unit. Thesecond image-quality adjustment unit is also activated at predeterminedtimes.

Because the features of the genuine toner are explicit, it can beexpected that images of a certain degree of high quality can be formed.Therefore, the image-quality adjustment using the above-describedelectrostatic latent image can help form high-quality images.

Accordingly, this multifunctional printer 10 can form images of as highquality as possible for the genuine toner.

It may be possible to set the first image-quality adjustment unit to beactivated more often than the second image-quality adjustment unit in apredetermined period. For example, the first image-quality adjustmentunit is set to be activated every time an image to be output is formed.On the other hand, the second image-quality adjustment unit is set to beactivated every time thousands of images are formed since the tonercartridge 24 has been loaded. Because the genuine toner has featuressuitable for the multifunctional printer 10, frequent image-qualityadjustments are not needed to form high-quality images. On the contrary,because the non-genuine toner does not have the features suitable forthe multifunctional printer 10, it is uncertain, even just after animage is output, whether the same quality image can be formed.

When the genuine toner cartridge 24 is loaded and completes theguaranteed number of pages that can be printed from the cartridge, itmay be possible to set the IC tag 26 to store the information about thecompletion of the guaranteed number of pages. FIG. 6 is a flow chartillustrating the operation of the controller 11 to complete thisprocess. Referring to FIG. 6, when the guaranteed number of pages thatcan be printed from the genuine toner cartridge 24 is completed (S21),the reader 25 accesses to the IC tag 26 attached on the toner cartridge24 (S22). Then, the reader 25 writes a value in a down counter providedin a storage area of the IC tag 26 to be incremented by 1 (S23). Thisdown counter is to be incremented by 1 upon completion of the guaranteednumber of pages and store the incremented value in the storage area ofthe IC tag 26. An initial count of the down counter is zero. In thisway, the down-counter information is rewritten and stored in the IC tag26.

This allows the controller 11 to read the down-counter information inthe IC tag 26 when a new toner cartridge 24 is loaded, and to determinewhether the toner cartridge 24 has been used to copy the guaranteednumber of pages. Some non-genuine products are made by refillingnon-genuine toner into a genuine toner cartridge 24 that has been usedto copy the guaranteed number of pages. In this case, since the genuinetoner cartridge 24 is refilled with the non-genuine toner, reading onlythe information stored in the IC tag 26 may cause the controller 11 tomake a wrong determination. However, the controller 11 can determinewhether the toner refilled in the toner cartridge 24 is non-genuine byreading the down-counter information.

By the way, in the case where the manufacturer of the multifunctionalprinter 10 collects empty genuine toner cartridges 24 and refillsgenuine toner into the cartridges, the down-counter information storedin the IC tag 26 is rewritten as well, and therefore the toner cartridge24 can be determined as a genuine toner cartridge.

In the above-discussed embodiment, the toner cartridge filled with toneris cited as a replaceable consumable, the present invention is notlimited to this and can be applied to the other consumables such as aphotoreceptor and a developing system incorporating a photoreceptor anddeveloping unit. Specifically, when a photoreceptor, which is aconsumable, is determined to be non-genuine, for example, the imageforming apparatus adjusts image quality by changing the amount of lightto be irradiated to the photoreceptor and the charge quantity of tonerwith respect to the setup programmed for a genuine photoreceptor inorder to obtain images of as high quality as possible.

In the above-discussed embodiment, the determination unit, whichcomprises an IC tag, a reader and a controller, determines whether theconsumable is non-genuine or not, the present invention is not limitedto this. The determination whether the consumable is non-genuine alsocan be made through other methods, for example, by providing adistinctive part to consumables and identifying the distinctive part bymeans of the controller.

Furthermore, the image quality is adjusted by supplying toner thatadheres to the electrostatic latent image used for adjusting the imagequality and comparing the toner densities to obtain the differencetherebetween in the above-discussed embodiment, however, the presentinvention is not limited to this. The image-quality adjustment can bemade through other methods. Yet furthermore, the description of theabove-discussed embodiment is made for an image-quality adjustment whentoner is determined to be genuine or not, however, the present inventionis not limited to this. When it is determined whether the photoreceptoris genuine or not, the image-quality adjustment also can be performed,for example, by measuring surface potential at several points on thephotoreceptor and comparing the surface potentials to obtain thedifferences thereamong.

Yet furthermore, the image forming apparatus can be set not to allow thefirst image-quality adjustment unit to adjust image quality when thereplaceable consumable is determined to be genuine.

The foregoing has described the embodiments of the present invention byreferring to the drawings. However the invention should not be limitedto the illustrated embodiments. It should be appreciated that variousmodifications and changes can be made to the illustrated embodimentswithin the scope of the appended claims and their equivalents.

1. An image forming apparatus comprising: a replaceable consumable; adetermination unit for determining whether said consumable isnon-genuine; a first image-quality adjustment unit for adjusting imagequality, wherein when said determination unit determines that saidconsumable is non-genuine, said first image-quality adjustment unitperforms an image-quality adjustment suitable for said non-genuineconsumable; and a second image-quality adjustment unit for adjustingimage quality, wherein when said determination unit determines that saidconsumable is genuine, said second image-quality adjustment unitperforms an image-quality adjustment suitable for said genuineconsumable, wherein said consumable includes a toner cartridge filledwith toner, said first image-quality adjustment unit adjusts imagequality by supplying non-genuine toner that adheres to a firstelectrostatic latent image including a plural number of pattern imagesand used for adjusting the image quality, said first electrostaticlatent image being formed on a photoreceptor, said second image-qualityadjustment unit adjusts image quality by supplying genuine toner thatadheres to a second electrostatic latent image including a plural numberof pattern images and used for adjusting the image quality, said secondelectrostatic latent image being formed on a photoreceptor, and thenumber of pattern images included said first electrostatic latent imageis larger than the number of pattern images included said secondelectrostatic latent image.
 2. An image forming apparatus comprising: areplaceable consumable; a determination unit for determining whethersaid consumable is non-genuine; a first image-quality adjustment unitfor adjusting image quality, wherein when said determination unitdetermines that said consumable is non-genuine, said first image-qualityadjustment unit performs an image-quality adjustment suitable for saidnon-genuine consumable; and a second image-quality adjustment unit foradjusting image quality, wherein when said determination unit determinesthat said consumable is genuine, said second image-quality adjustmentunit performs an image-quality adjustment suitable for said genuineconsumable, wherein said consumable includes a toner cartridge filledwith toner, said first image-quality adjustment unit adjusts imagequality by supplying non-genuine toner that adheres to a firstelectrostatic latent image including a plural number of strip-shapedpattern images and used for adjusting the image quality, said firstelectrostatic latent image being formed on a photoreceptor, said secondimage-quality adjustment unit adjusts image quality by supplying genuinetoner that adheres to a second electrostatic latent image including aplural number of strip-shaped pattern images and used for adjusting theimage quality, said second electrostatic latent image being formed on aphotoreceptor, and an area of pattern image included said firstelectrostatic latent image is larger than an area of pattern imageincluded said second electrostatic latent image.
 3. The image formingapparatus according to claim 1, wherein said first image-qualityadjustment unit is activated more often than the second image-qualityadjustment unit in a predetermined period.
 4. The image formingapparatus according to claim 2, wherein said first image-qualityadjustment unit is activated more often than the second image-qualityadjustment unit in a predetermined period.